Telegraph transmitter



Dec. 19, 1950 w. J. ZENNER 2,534,494

TELEGRAPH TRANSMITTER Filed Oct. 4, 1947 I 2 Sheets-Sheet -1 FIG. I

M LIB 12 I4 I? -l-2 INVENTOR WALTER J. ZENNER ATTORNEY Dec. 19, 1950 Filed Oct. 4, 1947 FIG. 4

FIG. 5

FIG. 3

W. J. ZENNER TELEGRAPH TRANSMITTER 2 Sheets-Sheet 2 INVENTOR WALTER J. ZENNER ATTORNEY Patented Dec. 19, 1950 TELEGRAPH TRANSMITTER Walter J. Zenner, Des Plaines, Ill., assignor to Teletype Corporation, Chicago, 111., a corporation of Delaware Application October 4, 1947, Serial No. '77 8,005

4 Claims.

This invention relates to printing telegraph transmitters and more particularly to a push button keyboard transmitter adapted for use with systems in which the signals comprise permutations of two different circuit conditions.

It is an object of this invention to provide a keyboard wherein the keys are in the form of push buttons, which position a set of code or permutation bars in different combinations.

Another object of the invention is to provide a low cost transmitter wherein push buttons having cone shaped lower ends are adapted to engage in succession apertures of progressively smaller diameter in a series of nested code or permutation bars whereby the bars are shifted into predetermined combinations Another obect of this invention is to provide a series of code bars, each having a finger thereon which controls a circuit closing means in accordance with the position of the finger Another object of this invention is to provide a printing telegraph transmitter apparatus wherein the depression of a key permutates a set of code bars, and a lever, actuated due to the depression of the key, engages a finger on each code bar to lock the code bars in their permuted positions.

Other objects and advantages of the invention will be apparent and the invention will be more readily understood from the following description when read with reference to the accompanying drawings, in which:

Fig. 1 is a top plan View of a printing telegraph transmitter partly cut away to show the improved keyboard controlled mechanism embodying the principal features of the invention;

Fig. 2 is a side elevation partly in section taken along the line 22 of Fig. 1;

Fig. 3 is an enlarged fragmentary view showing the space bar mechanism in detail;

Fig. 4 is a fragmentary sectional view taken along the line 4-4 of Fig. 1; and

Fig. 5 is a fragmentary sectional side view of the upper portion of the keys.

In the drawings, the apparatus has a metal base or frame ID with a front portion ll thereof, in which a keyboard I2 is mounted, whereby a top plate l3 of the keyboard I2 is secured to the front portion of the base Ii! by screws [4. The top plate I3 is provided with spaced apertures therein through which a set of reciprocatory keys or push buttons l6 protrude. A space bar I1 is reciprocably mounted in a longitudinal slot (not shown) in the top plate [3. End plates I8 are fastened to the top plate [3 of the keyboard by screws l9 and a base plate is secured to the end plates I8 by screws 23. The base plate 20 is provided with spaced apertures (not shown) which are of smaller diameter than, but aligned with, the spaced apertures IS in the top plate l3.

The keys 16 are in the form of push buttons and have cone shaped central portions 24. The lower portions 25 of the keys are rod shaped and etxend through the spaced apertures in base plate 26. A helical spring 26 surrounds the rod shaped portion 25 of each key and abuts the base plate 23 and a collar 21 on the rod shaped portion. The ends of the rod shaped portions extend through the apertures in the base plate 20 and are threaded to accommodate nuts 28 which prevent the springs 26 from withdrawing th keys from the base plate. Anti-noise washers 29 surround the rod shaped portions 25 of the keys and act as buffers between the nuts 28 and the base plate 20. Collar like lugs 3!! around the keys l6 and beneath the top plate l3 prevent the springs 26 from throwing the keys out of th keyboard and felt washers 3| serve to prevent noise and act as shock absorbers between the collar like lugs and the top plate.

A series of five nested code bars or plates 32 of channel form are slidably supported on frictionless bearings 33 and 34 and laterally spaced thereon by frictionless spacers 35 The frictionless bearings 33 and spacers 35 are alternately spaced on a threaded bolt 36 protruding from each end plate [8 and are held in place thereon by lock nuts 3'! and 38. Th frictionless bearings 34 are spaced by lock nuts 40 and 4! on a threaded bolt 39 which also protrudes from each end plate l8. Eccentrics 42, fastened to the end plates l8 by screws 43, hold the code bars 32 against the frictionless bearings 33 and 34.

Each code bar 32 has apertures 44 therein corresponding to each key IQ of the keyboard l2, the size of the apertures 44 in each succeeding nested code bar 32 becoming progressively smaller to correspond with the reducing diameter of the cone portions 24 of the keys !6 Each aperture 44 is laterally aligned with its corresponding key [6 but is longitudinally spaced in one of two positions in order that the code bar 32 will be moved longitudinally to one of two positions when any particular key [6 is depressed. When a key I6 is depressed the cone portion 24 thereof engages the periphery of the corresponding apertures 44 to cam each code bar 32 longitudinally and set up that permutation of positions of all the code bars 32 which corresponds to the particular key depressed.

Referring to Fig. 3, a pair of rods 48 are secured to the keyboard top late l3 by screws 49 and extend to the base plate 20. A space bar guide plate 50 is secured to the base plate 20 by screws 5I which extend transversely through the space bar guide plate, and through the base plate 29, into the rods 49. A flat space bar support 52 extends through and is reciprocable in the longitudinal slot (not shown) in the top plate I3. The space bar support 52 is provided with tapered cam surfaces 53 and a depending portion 54 is engaged and guided by a pair of guide rollers 55 which are bolted to the space bar guide plate 59; The upper end of a tension spring 56 is fastened to a lug ti on the top plate I3 and the other end is fastened to the space bar'support 52 by a bolt in Fig. 2) is threaded into the depending'portion' 54 of the space bar support and engages an antinoise pad (not shown) on the bottom of the base plate 29 to prevent the spring 5 3 from throwing the space bar I? out of the keyboard.

U-shaped levers 69 are pivotally secured to the space bar guide plate 59 by a pair of bolts 53. When the space bar I'I is depressed the tapered cam surfaces 53 on the space bar support 52 engage the levers 69 to pivot them on their supporting bolts 93; whereby the levers 6i) engage the edges 64 of notches in the code bars 32 to move the code bars longitudinally so that the permutation of positions thereof will correspond to the space code combination.

Referring to Fig. 4, each code bar 32 is provided with a cut-out 61 in the edge thereof and a finger 98 protrudes from each code bar within this cutout 67. A V-shaped locking finger69'also protrudes from each code bar 32 within another cut-out ID.

A pair of brackets 89 is secured to the metal base II) by bolts 8|,and has a shaft 82 journaled therein. A driven gear (not shown) is pinned to the shaft 82 and meshes with a coacting drive gear 83, which is pinned to a continuously rotating drive shaft 94. The drive shaft 84 is journaled in a bracket 85 which is secured to the metal frame I9 and is driven by an electric motor, not shown. A transmitter cam drum 86 is adjustably keyed to the shaft 32, and is held in adjusted position thereon by a nut 88 which engages a set of threads 89 in a spacer collar 81 pinned to the shaft. A keyboard clutch 99 of the one revolution type has a driven member 9| which is keyed to the transmitter cam drum 89 but longitudinally slidable thereon, and a drive member 92 which is pinned to the shaft 82 by a screw 93. A helical compression spring 94 abuts a collar 95 on the driven member 9! and a collar 96 on the transmitter cam drum 83, to force the driven member into engagement with the drive member 92. The driven member 9I is provided with a throw-out cam 97 and a start-stop cam 98 which control the operation of the keyboard clutch 99.

A pair of lugs I99 fastened to the frame-I9 pivotally supports a universal bail I9I' which is adapted to pivot downwardly whenever a key I 5 or the space bar I I is depressed. A set of'cross bars I92 on the universal bail IEH is aligned with the rows of keys I9 so that when a key is depressed the rod-shaped portion thereof will engage one of these cross bars and thus pivot the universal bail. When the space bar I1 is depressed the stud 59 will engage one of the cross bars I52 to pivot the universal bail I 9|. A stop I99 (Fig. 4) is fastened to the base plate 29 to limit the upward movement of the universal bail I M and a set screw I94 limits the downward movement thereof.

A rocking lever I95 is fastened to the universal bail IOI and a clutch releasing lever IDS is pivotally supported on the rocking lever by a bolt I91. The clutch releasing lever I06 extends beneath the start-stop cam 93 of the driven member 9I, and a tooth (not shown) on the clutch releasing lever engages a clutch throw-out lever I98 which in'turn engages the throw-out cam 91 on the driven member 9I. The clutch releasing lever I96 is held against the start-stop cam 98 and clutch throw-out lever I99 by a tension spring I99, which is fastened to the clutch releasing lever'and to a lug (not shown) protruding from the rocking lever I95. Thus, whenever a key It or the space bar I! is depressed, the universal bail IIlIpivots, the rocking lever I moves forward pulling the clutch releasing lever I96 forward, and the tooth on the clutch releasing lever engages the clutch throw-out lever I98 to move it from engagement with the throw-out-cam' 97 0115171716 driven clutchmember 9|. The helical spring 94 then forces the driven member 9I into engagement withthe drive member 92 and the transmitter cam drum 86 rotates. The transmitter cam drum 86 rotates through only one revolution because the high portion of the start-stop cam 99 causes the clutch releasing lever I96 to pivot, thereby causingithe tooth on the clutch releasing lever to become disengaged from clutch throw-out lever I98. The clutch throw-o'ut'lever I98 then'returns to the normal position whereby it-re-engages thethrow-outcam 91 to force the driven member 9| from engagement with the drive member "92.

A metal support II2 is secured'to the frame I9 by screws II3. A set of circuit makers or contact levers ll4cand'a locking lever I I6, in the form of bell cranks',.and a start contact lever II 5 are mounted on a' common pivotal support I I? which extends longitudinally through the metal support I I2, and are freely pivoted within transverse slots (not shown) in the metal support. A comb bar H8 ismounted on the top plate I3 ofthekeyboard by bolts II9', and has a series of slots I2-9th'erein for guiding the contact levers IM and the locking lever H6.

The horizontal arms of the contact levers H4 extend forward to beneath the cut-out portions 61 of the nested code bars '32 and are adapted to either engagethe set fingers 68in the code bars or to pivot upwards within thecut-out portions, according to'the positions of the code bars as determined by the particular key I6 depressed to set the code bars.

The transmitter cam drum 86 is divided into camsections I23 and a start-stopcam I24 which cooperates with the contact levers II4 and start contact lever II5, respectively. A lug I25 on the vertical arm of each contact lever IM or II5 coacts with its corresponding cam section I23 or start-stop cam I24. A set of spring contact fingers I25 and aset of cooperating contact fingers I21 which are connected to 'a signal line circuit (not shown) are mounted upon but are insulated from the support I I2. Each spring contact finger I29 tends to engage its associated contact finger I2 and also presses against the upper extremity I29 on each of the contact levers H4 and M5 to hold. the lug I25 of each contact lever in engagement'with its corresponding cam section I23 or start-stop cam I24.

A locking cam I29 mounted on'the-transmitter cam drum 8'9 coacts with a roller I39, which is mounted on the verticalarm of the locking lever IIB by a bolt I3I1 A tension spring I32, carried by anarm I33, which arm is secured to the supstart-stop cam port II2 by a screw I34, holds the roller i3G against the locking cam I29. The horizontal arm of the locking lever IIB extends forward to beneath the cut-out portions in the code bars 32 where-it has two cam surfaces I35 (shown more clearly in Fig. 4) which cooperate with the locking fingers 69 of each code bar. The cooperation between the cam surfaces I35 of the locking lever H6 and the locking fingers 69 is such that the code bars 32 are locked in that particular permutation of positions which corresponds to the key I6 depressed.

The low portions of the cam sections I23 and I24 are sequentially spaced around the periphery of the transmitter cam drum 8%. When the apparatus is in operation,

but at a time when neither a key I6 nor the space bar I? is depressed (the condition of the apparatus as shown in Fig. 1), the transmitter cam drum 8%; is stationary, and the low portion of the start-stop cam I2 3 is adjacent the lug I25 on the start contact lever H5. Thus, the spring contact finger I28, which cooperates with the start contact lever H5, forces the lug I25 into engagement with the low portion of start-stop cam IN and also engages its associated contact finger I27 to close the circuit. Also at the time when the transmitter cam drum 8% is stationary, the high portion of the locking cam i2 engages the roller I30, which pivots the horizontal arm of the locking lever IIG, whereby the cam surfaces E35 on the locking lever are withdrawn from engagement with the locking fingers as on the code bars 32.

When a key It or the space bar It is depressed, the one revolution keyboard clutch 96 is actuated which causes the transmitter cam drum 8% to rotate, and the cone-shaped portion 25 of the particular key depressed or the tapered cam surfaces 53 of the space bar support 52 cause the code bars 32 to shift longitudinally, thus setting the correct permutation of the set fingers 63. With the transmitter cam drum 86 having thus been set in motion, the locking roller I3il is riding on the low portion of the locking cam 52?), which allows the tension spring I32 to raise the locking lever IIE until its cam surfaces i3ii engage the locking fingers 69 to lock the permuted code bars 32. Also, during the rotation of the transmitter cam drum 86, the high portion of the start-stop cam I24 engages the lug M5 on the start contact lever II5, whereby the corresponding spring contact finger I28 is thrown out of contact with its associated contact finnger I27, and the circuit is thus thrown open. The low-portions of each cam section l23 are sequentially rotated to a position adjacent the corresponding lug I25 on each contact lever I I4, whereby the corresponding spring contact finger I26 tends to force the lug into engagement with the low portion of the corresponding cam section, which allows the spring contact finger to engage its corresponding contact finger to momentarily close the line circuit. Whenever a set finger 68, on one of the code bars 32 is aligned with its corresponding contact lever l M, the corresponding spring contact finger I2ii is prevented from forcing the lug I25 against the low portion of the adjacent cam section I23 and thus the circuit remains open. Therefore, this apparatus converts the permutation of positions of the code bars 32, which corresponds to the particular key iii or space bar I? depressed into a definite series of electrical impulses in the circuit, which can be received and printed by the local telegraph printer or by a printer at a distant receiving apparatus or which can be used by a tape perforating apparatus to perforate a tape.

This invention has been described in connection with a specific embodiment thereof but is capable of modification without departing from the spirit or scope of the invention, and is to be considered as limited only by the scope of the appended claims.

What is claimed is:

1. In a telegraph apparatus, a keyboard, a plurality of push button type keys mounted in said keyboard, a space bar mounted in said key,- board, a plurality of channel shaped movable code plates each having apertures therein corresponding to each of said keys, cam surfaces on each of said keys being adapted to enter the corresponding aperture in each of said code plates whenever a key is depressed to cam said code plates into a permutation of positions corresponding to the key depressed, a cam surface on said space bar being adapted to shift said code plates into a permutation of positions corresponding to a space whenever said space bar is depressed, a locking finger on each code plate, a lever actuated whenever one of the keys or the space bar is depressed for engaging said locking finger on each code plate to lock said code plates in the permutation of positions corresponding to the key or space bar depressed, a finger on each code plate and movable therewith to either a circuit making position or to a noncircuit making position whenever said code plates are permutably positioned, and a plurality of circuit makers which normally sequentially close a circuit, each of said circuit makers cooperating with one of said fingers whereby the permutation of positions of said code plates is converted into a permutation of open and closed circuit conditions.

2. In combination, a keyboard, a plurality of depressible keys in said keyboard, a plurality of nested code plates movable to permutations of positions corresponding to each of said keys, said code plates each having a plurality of openings, said openings being provided in each of said code plates corresponding to each of said keys, and cone shaped portions on each of said keys for entering the corresponding opening in each of said code bars upon depression of one of said keys to cam said plurality of code bars to the permutation of positions corresponding to the depressed key, said openings in successive code bars becoming progressively smaller in the direction of depression ofsaid keys whereby the permutation of said code bars corresponding to the depressed key is set up only upon full depression thereof.

3. In a telegraph transmitter, a keyboard, a plurality of depressible keys in said keyboard, a plurality of code bars movable to permutations of positions corresponding to each of said keys, said code bars each having a plurality of openings, said openings being provided in each of said code bars corresponding to each of said keys, cone shaped portions on each of said keys for entering the corresponding opening in each of said code bars upon depression of one of said keys to cam said plurality of code bars to the permutation of positions corresponding to the depressed key, said openings in successive code bars becoming progressively smaller in the direction of depression of said keys whereby the permutation of said code bars corresponding to the depressed key is set up only upon full depression thereof, a set of transmittingcontacts, and=means effective upon full depression ofone of said keys to cooperate With said apertures to cam each of said code plates to either of said two positions only upon full depression of such key.

WALTER J. ZENNER.

REFERENCES'IJITED ,The following, references are of recordin the Jim of this patent:

UNITED STATES PATENTS Number Name Date 1,533,206 Pfannenstiehl Apr. 14,1925 11,884,807 Morton Oct. 25, 1932 1,969,978 :I-Ianel Aug. 14, 1934 1,975,367 Mavs Oct. 2, 1934 2,135,377 Dirkes Nov. 1, 1938 2,170,100 Terjeson Aug. 22, 1939 "2,212,548 Noxon "Aug; 27,. 1940 2,255,201 7 Wheelock "Sept. 9, 1941 2,264,186 Noxon ,Nov. 25, 1941 2,408,754 Bush Oct. 8, 1946 

